7JSW
ArfB Rescue of a 70S Ribosome stalled on truncated mRNA with a partial A-site codon (+2-III)
This is a non-PDB format compatible entry.
Summary for 7JSW
| Entry DOI | 10.2210/pdb7jsw/pdb |
| EMDB information | 22461 |
| Descriptor | 50S ribosomal protein L2, 50S ribosomal protein L16, 50S ribosomal protein L17, ... (54 entities in total) |
| Functional Keywords | ribosome, arfb, mrna, translation, ribosome-translation complex, ribosome/translation |
| Biological source | Escherichia coli K-12 More |
| Total number of polymer chains | 54 |
| Total formula weight | 2149901.33 |
| Authors | Carbone, C.E.,Korostelev, A.A. (deposition date: 2020-08-16, release date: 2020-11-11, Last modification date: 2024-03-06) |
| Primary citation | Carbone, C.E.,Demo, G.,Madireddy, R.,Svidritskiy, E.,Korostelev, A.A. ArfB can displace mRNA to rescue stalled ribosomes. Nat Commun, 11:5552-5552, 2020 Cited by PubMed Abstract: Ribosomes stalled during translation must be rescued to replenish the pool of translation-competent ribosomal subunits. Bacterial alternative rescue factor B (ArfB) releases nascent peptides from ribosomes stalled on mRNAs truncated at the A site, allowing ribosome recycling. Prior structural work revealed that ArfB recognizes such ribosomes by inserting its C-terminal α-helix into the vacant mRNA tunnel. In this work, we report that ArfB can efficiently recognize a wider range of mRNA substrates, including longer mRNAs that extend beyond the A-site codon. Single-particle cryo-EM unveils that ArfB employs two modes of function depending on the mRNA length. ArfB acts as a monomer to accommodate a shorter mRNA in the ribosomal A site. By contrast, longer mRNAs are displaced from the mRNA tunnel by more than 20 Å and are stabilized in the intersubunit space by dimeric ArfB. Uncovering distinct modes of ArfB function resolves conflicting biochemical and structural studies, and may lead to re-examination of other ribosome rescue pathways, whose functions depend on mRNA lengths. PubMed: 33144582DOI: 10.1038/s41467-020-19370-z PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.8 Å) |
Structure validation
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